The 19-year-old academy product made five appearances on the wing early in the season but has started the last three matches at full-back.
The Wolves have also handed two-year contract extensions to Ellis Longstaff and Connor Wrench and new 12-month deals to Riley Dean, Eribe Doro and Jacob Gannon.
Dean is currently on loan at Championship club York and will stay there for the rest of the season before rejoining the first-team squad for 2022.
Warrington coach Steve Price said: “It’s very promising for all of these younger players to have re-signed with the club.
“It’s important they keep their heads down now and work extremely hard on their game to keep improving.
“Josh is an exciting, hard-working young kid who has got a very bright future. He understands what he needs to do to keep evolving his game and is very driven for success.
“I’m really pleased with how Connor is progressing. He’s got a lot of great athleticism and is a local kid with a big future in the Wire colours.
“Ellis is a strong back-rower who plays the game tough. He’s got a lot of good rugby smarts about him and is going to be a really good long-term player for our footie club.
“Eribe is an exciting ball carrier. There are areas of his game which he’s working hard to improve on and there’s plenty more to come from him in the years ahead.
“Riley is a player who can play a number of positions which is really important in today’s game. He’s been impressive while out on loan at York this season and I’m looking forward to seeing him grow his game.
“Jacob’s still learning his craft and it’s unfortunate that he’s had to miss a lot of footie since the pandemic began. He’s another exciting middle and I’m looking forward to seeing him develop.”